Energy Consumption Costs and Problems
Energy consumption in commercial buildings is a very expensive component of the cost for operating and maintaining a building. For example, commercial buildings have expensive air conditioning and heating needs which over the lifetime of the building often add up to more than double the first cost for construction. Attempts over the years to reduce energy consumption have resulted in adding substantial increases in construction costs which are not recouped over the short term.
The typical commercial building heating and cooling system used in the U.S. today is a Variable Air Volume (VAV) system, typically configured this system cannot utilize sustainable energy sources. Buildings represent 40% of the energy used in the U.S. and are fueled almost entirely with fossil fuels that are expensive and damaging to the environment. There are a number of problems that make these HVAC systems energy inefficient, unhealthy, uncomfortable, and that create barriers to adopting new technologies. These problems include:                Pressure on construction costs encourages owners to keep up front costs low by purchasing inexpensive, wasteful HVAC systems        Wasting excess energy rejected through chillers, etc. rather than moving it to where it is needed or storing it for later use        High energy movement through walls because of inadequate insulation—in conventional systems the shell is not part of the solution, but in the invention it can be made to be an energy storage device        Constantly reheating and re-cooling the building mass rather than holding it at temperature        Overbuilt, inefficient systems that could be made much smaller        The inability to use local energy (e.g. solar, body heat, etc.)        Heating the building when the heating system is least efficient and likewise cooling the building when the cooling system is least efficient—with energy storage, this can be reversed to increase efficiency        Geothermal systems are typically more costly to build and their function is not designed to maximize efficiency which in turn reduces the use of these systems        
The rapidly changing alternative energy technologies that are being developed are created in silos to perform the functions of that technology and do not work together without custom integration. These often prove to be unreliable or fail. Few engineering firms have the resources to research and integrate innovative solutions and as a result do not commonly design them into client buildings. This is the way that air conditioning units were built before Carrier standardized the A/C unit which is described in U.S. Pat. No. 2,154,263 in which Willis Carrier patented a standard refrigeration unit for a rail car. The custom-build process is very expensive and limits market use while the standardized product brings down costs and expands the market.
While we are aware that there is a great deal of energy available locally (e.g. body heat, lighting heat, computer heat, solar thermal, solar photovoltaic, geothermal, etc.) the U.S. has failed to adopt a significant use of local energy harvesting (i.e. alternative or renewable energy). According to the U.S. Department of Energy, in September of 2009, alternative energy accounted for less than 1% of the energy used in the U.S. In order to use local energy harvesting the building must have a system capable of sensing the availability of different types of energy and of transporting that energy to where it is needed.
To make that device cost effective, it must be manufactured inexpensively enough to be affordable at a comparative cost to a conventional HVAC system. Further, in order to make alternative energy equipment affordable it must have a longer range of operation (i.e. use energy storage) than that of the intermittent energy sources it attempts to use (e.g. the sun sets, people leave a building, lights are turned off, etc.). That intermittent availability can be extended by storing the thermal energy and this in turn increases the return on investment made in the energy harvesting equipment.
Therefore, designing the energy sensing, harvesting, storage, transportation and controls as a single system capable of connecting a multitude of sources to a multitude of uses enables the efficient application of alternative energy and increases the return on investment in the required equipment in order to make it affordable at the current market cost threshold for HVAC equipment.
Geothermal Heat Pump/Heat Exchanger Costs and Problems
Typical geothermal heat pump heat exchangers come in various configurations including vertical closed loop, horizontal closed loop, “Slinky” loop, pond loop, thermal piles, etc. but generally when applied to a system these configurations have the following characteristics:
1. A single fluid circuit is applied (e.g. a vertical loop is not combined with a horizontal loop)
2. The fluid in the single fluid circuit is mixed and delivered to all heating/cooling devices at a constant temperature. This is the case with U.S. Pat. Nos. 7,571,762 and 7,407,003 issued to Ross, where both devices manifold all the geothermal bores together mixing the fluids. This mixing of temperature dilutes its ability to transfer heat as a result of a reduction of the temperature difference between the fluid and the terminal heat transfer device. The greater the temperature difference, the greater the heat transfer and conversely less temperature difference means less heat transfer.
Current geothermal heat exchanger design is not optimized to provide cooler water to support sensible cooling devices such as radiant cooling panels and chilled beams. Instead, they mix higher and lower temperature water together which reduces the ability to provide sensible cooling with these devices. Additionally, current geothermal heat exchanger design is not configured to maximize the ability to store energy for later use by mixing/combining various heat exchanger configurations.
Previous art includes combinations made of multiple types of alternative HVAC equipment such as Nishman U.S. Pat. No. 4,375,806 which combines a geothermal system with a solar hot water panel and a system of sensors, circuits, and controllers that only uses the solar panel and geothermal system in combination when it is efficient. Nishman's claims were for a system that simply turned two sources on or off based on real time (only) efficiency of the two devices (rather than improving efficiency of the entire system over time). The present invention goes beyond Nishman, with both sources controlled individually to be able to use each source at a variable level to optimize the complete system.
The Ross '762 and '003 patents presents a geothermal manifold which allows geothermal loops to be piped in parallel to each other. This method does not allow for loops to be separated for different uses; it combines all inputs and all outputs into a two pipe (one in, one out) system. The invention entailed herein uses automated selection of the best loop(s) to use, and can use loops in different modes simultaneously, can use different types of loops simultaneously, or mix loop fluids as desired for efficiency. Unlike Ross, the present invention has the ability to efficiently heat and cool at the same time. It can achieve this via a heat pump or directly from a dedicated hot thermal energy storage and a dedicated cold thermal energy storage simultaneously.
U.S. Pat. No. 4,360,056 issued to O'Connell on Nov. 23, 1982 teaches a system with multiple geothermal loops which are pumped separately. This system still combines or mixes all the geothermal fluids into a single fluid circuit (piped) system with only one inlet and one output. This does not allow for multiple temperature fluids to be used at the same time, a functionality that improves energy efficiency.
U.S. Pat. No. 5,934,369 issued Dosani on Aug. 10, 1999 describes a method and controller for predicting the charging loads and time for thermal energy storage/thermal slabs. Unlike Dosani, the present invention goes beyond this previous art. This prediction and knowledge of thermal energy storage is useful yet it is only fully utilized when combined with building load predictions, on-peak/off-peak electrical cost rate structure, and controls of sources and sinks as the invention herein covers.
U.S. Pat. No. 5,778,683 issued to Drees on Jul. 14, 1998, titled “Thermal storage system controller and method” teaches a utility rate with a peak rate structure; it does not entail thermal storage for reduction of system size and for increasing the availability of sustainable energy as the present invention does. Drees entails a data structure of the utility rate structure and determines the relative cost-effectiveness of using thermal storage versus non-thermal storage and also how much of the thermal storage capacity can be used. It does not cover the thermal capacity and charge/discharge rate predictions/measurements that Dosani does. As it does not combine these inputs, it cannot reach the most efficient energy use solution. The present invention does have the additional functionality to create the most efficient energy system. The present invention also includes the system design function to increase efficiency savings by predicting the thermal storage performance along with a matrix of other factors which allow the system to be properly sized and not waste first cost capital on an over sized, less efficient HVAC system.
The need exists for solutions to the above problems with the prior art.